How AI in Games Works

Introduction to Gaming AI

You probably don’t think that the average rabbit is particularly intelligent. They generally like eating grass, hopping around and digging holes. How complicated could such a small animal be?

Well, in early 2008, IBM embarked on a project to digitally simulate the cerebral cortex of such a small mammal at the Thomas J Watson Research Center. The test used 8,192 processors and 2.8TB of memory on the Blue Gene-L supercomputer to simulate the 22 million neurons and 11 billion synapses found in the16cm2 cortical surface of a rabbit’s brain.

Simulating even primitive intelligence is extremely demanding, so how does a basic PC go about simulating human intelligence in multiple game characters at once?

Gaming AI is in many ways similar to 3D graphics rasterisation, which uses complex trickery such as shaders and textures to give the impression of real light and shadow. If you were to properly ray trace a 3D scene in a game, as you would in a CGI movie, it would take considerably more processing power, and the same applies to AI.

Empire Total War features thousands of men on screen at once. All need to have a degree of intelligence to make the game playable.

Creative Assembly’s AI programmer, Richard Bull, who masterminded the battle AI system in Empire: Total War explains that "the AI academics are your wizards and we’re your stage magicians – it’s all smoke and mirrors with game AI.

"We’re trying to give you the perception of reality, and often we therefore look like we’ve got systems that are much more impressive than anything the academics can create, and we’re not doing anything more intelligent. In fact, in most cases, we’re not – what we’re doing is giving the perception of the AI being much cleverer than it actually is."

When an enemy in F.E.A.R. kicks you as you move closer and then dives through an open window, it gives you the impression that it’s a real human character wanting to kill you and survive, but all it’s really doing is responding to a computer program and using the right animations at the right time. Unwrapping gaming AI is rather like watching the camera zoom out to reveal Frank Oz controlling Miss Piggy; it’s disappointing at first, but becomes incredible when you see the amount of work that goes into the puppetry.

The exponential rise in computing power has led to many big steps forward in the world of Artificial Intelligence. Mark Mackay examines some of the research that is being done in this area and looks at what the future might hold for all of us.

The Twilight of Peace is over! Space Marines line the horizon as the sun rises behind them, ready to face off against the coming swathes of Tyranids. This is the advent of a new age; the Dawn of War...again. We take a look at Relic's latest strategy opus to see if it's any good.

The Total War series is very highly regarded at bit-tech and Empire: Total War, the next game in the series, is just a few months away from release. We visited The Creative Assembly earlier this month to see how the game is shaping up. Read on to find out what we thought...

Soulstorm is the latest and last of the Dawn of War expansions, delivering a standalone strategy game that delivers new races, units and tech trees. The last game developed by Iron Lore Studios, can the fighting nuns of Soulstorm provide a decent legacy?

We take the latest expansion pack for F.E.A.R. out for a spin to see how TimeGate has carried on the work of Monolith with the classic Horror/Shooter franchise. Is the game any good or is it just a slew of clichés and pastiches? We find out!